1. Field of Invention
This invention relates to miniaturized, slide-action electric switches of the type employed for switching devices on television and radio sets and the like and in particular to such switches which are caseless in that they do not require the use of an outer metal casing.
More specifically, the invention relates to miniaturized, caseless electric switches of the above generally described type which employ a minimum number of parts and are comparatively easy and inexpensive to manufacture and sell and yet are reliable in operation.
2. Prior Art Problem
U.S. Pat. No. 3,983,341--issued Sept. 28, 1976; U.S. Pat. No. 4,016,378--issued Apr. 5, 1977 and U.S. Pat. No. 4,052,580--issued Oct. 4, 1977 all describe miniaturized electric switches of the above generally described type which do not require the use of an external metal casing or housing and hence are lighter and cheaper to manufacture and sell than similar switches which do require the use of an external metal casing such as those described in U.S. Pat. No. 3,072,757--issued Jan. 8, 1963, for example. Similar miniaturized, caseless electric switches are described in West German Utility Model Application (Gebrauchsmuster) No. 7344516 published Mar. 28, 1974 and in Japanese Utility Model Publication No. 13168/74 published Apr. 1, 1974. All of these known prior art patents and publications disclose miniaturized, caseless electric switches which employ a relatively thin, flat insulator base member of molded thermoplastic or the like on which electric terminals are mounted. A molded plastic slide housing having yieldable side skirts with hooks on the end thereof snaps over the base member and contains a slidable contact member which then is slid back or forth over the base member to actuate the switch. A difficulty encountered with the known switches of this design, is that the relatively thin, flat insulator base member is comparatively weak and is subject to fracture or bending during operation of the switch in service.
U.S. Pat. No. 4,016,401--issued Apr. 5, 1977, describes a miniaturized, caseless electric switch which utilizes both an insulator base member and slide housing of molded plastic construction both of which are of substantial thickness and not readily bent or fractured. However, the electric switch described in this patent requires a specially designed annular switch contact and elastically yieldable positioning element arrangement in addition to the requirement of a complex configured and expensive-to-mold shape for both the base insulator and slide housing members. Consequently, the switch is comparatively more expensive to manufacture and sell than the switches described in the preceding paragraph. The present invention was devised in order to overcome the objections to the above briefly described prior art miniaturized, slide-action, caseless electric switches, and to make available to the art an improved, low cost, slide-action, caseless switch which overcomes the objectionable features of the known designs and yet is relatively inexpensive to manufacture and assemble.